Applying tool for wire-type clamp

ABSTRACT

A tool for tightening and clamping around a pipe coupling a single strand of wire formed in two laterally spaced loops connected at one end by an integral bight, with the free shanks of respective loops underlying the bight. The tool comprises a threaded shaft rotatably supported in a frame which has a fulcrum foot at one end for pivotal engagement with the bight between the spaced loops. A pair of shank-gripping blocks are mounted on either side of the shaft for independent, longitudinal, sliding movement with respect to the shaft. A pulling block is threadedly mounted on the shaft and is connected to the gripping blocks by a flexible, load-equalizing cable running freely through an arcuate groove in the pulling block, with opposite ends of the cable secured to respective gripping blocks. The threaded shaft is rotatable by a handle to retract the pulling block longitudinally on the shaft and thereby exert independent pulling force on the respective gripping blocks and, in turn, on individual shanks of the wire loops. When the respective loops have been tightened to the desired extent, the bodily rotation of the tool about its fulcrum bends the wire shanks over the bight and clamps the loops around the pipe sections. Means are provided for cutting off the excess lengths of the shanks after clamping.

United States Patent [72] Inventors Barry J. Blumenfeld Randalktown;Charles K. Mauer, Baltimore, both of, Md. [21 Appl. No. 873,365 [22]Filed Nov. 3, 1969 [45] Patented Aug. 3, 1971 [73} Assignee Cast IronSoil Pipe Institute Washington, D.C.

[54] APPLYING TOOL FOR WIRE-TYPE CLAMP l 1 Claims, 7 Drawing 16 [52]U.S. 140/123, 81/93 [51] lnt.Cl 821115/02 [50] Field of Search 140/123,93.2, 93.4,102.5;81/9.3

[56] References Cited UNITED STATES PATENTS 784,114 3/1905 Moock 81/9.32,421,878 6/1947 Gubser et al.. 140/123 2,208,134 7/1940 McAneny, Jr.81/9.3 2,681,580 6/1954 Dupkas 8 H93 2,422,039 6/1947 Pritchard 81/9.3

FOREIGN PATENTS 572,264 10/1923 France 8 l/9.3

Primary Examiner-Charles W. Lanham Assistant Examiner-Michael J. KeenanAttorney-Raphael Semmes ABSTRACT: A tool for tightening and clampingaround a pipe coupling a single strand of wire formed in two laterallyspaced loops connected at one end by an integral bight, with the freeshanks of respective loops underlying the bight. The tool comprises athreaded shaft rotatably supported in a frame which has a fulcrum footat one end for pivotal engagement with the bight between the spacedloops. A pair of shankgripping blocks are mounted on either side of theshaft for independent, longitudinal, sliding movement with respect tothe shaft. A pulling block is threadedly mounted on the shaft and isconnected to the gripping blocks by a flexible, load-equalizing cablerunning freely through an arcuate groove in the pulling block, withopposite ends of the cable secured to respective gripping blocks. Thethreaded shaft is rotatable by a handle to retract the pulling blocklongitudinally on the shaft and thereby exert independent pulling forceon the respective gripping blocks and, in turn, on individual shanks ofthe wire loops. When the respective loops have been tightened to thedesired extent, the bodily rotation of the tool about its fulcrum bendsthe wire shanks over the bight and clamps the loops around the pipesections. Means are provided for cutting off the excess lengths of theshanks after clamping.

Patented Aug. 3, 1971 3,596,686

2 Sheets-Sheet 1 l "1 2/ iui 34 25 4/ 27 I 'uwgmrofls 5 3 BARRY JBLUMEWFELD CHARLES K. MAUER ATTORNEY Patented Aug. 3, 1971 3,596,686

2 Sheets-Sheet 21 //vv/vr0/?s BARRY J BLUMENFELD CHARLES K. MAUER BYQWXW A TTORNEY APPLYING TOOL FOR WIRE-TYPE CLAMP BACKGROUND OF INVENTIONNumerous wire clamp applying tools are conventionally used fortightening wire loops around pipe couplings and hose couplings,operating on the same basic principle as the present invention. However,none of the tools with which we are familiar are provided with means tocompensate for such conditions as differences in tolerances of two pipesbeing connected, differences in diameters of two edges or sides of theclamp, and differences in the length of the wire shanks being pulled totighten the wire loops around the pipe coupling. In all of theseconventional tools, the shanks of the wire loops are anchored in thethreaded head operated by a rotatable threaded shaft and operate, whenretracted, to directly uniformly contract the two wireclamping loops.

In other words, an equal pulling force is applied to the shanks of bothloops so that diflerences in tolerances, for example, of the pipes beingcoupled are not compensated for, and an insufficient clamping force maybe applied to one or the other of the sections of pipe.

The present invention is designed to overcome this difficulty and hasfor its object to provide a wire clamp applying tool having equalizingmeans to automatically compensate for tolerance differences as the loopsare being tightened and clamped.

Another object of the invention is to provide a tool having separate andindependent shank-gripping means for the respective loops of wire and apulling force equalizing block for controlling the pulling force exertedon the respective gripping blocks.

Still another object of the invention is to provide novel and easilyoperable gripping cam means for anchoring the shanks of the wire loopsencircling the coupling during the tightening operation.

Another object is to provide a tool of this character which incorporatesa shank-cutting element for disposing of the excessive lengths of wireloop shanks after the loops have been tightened and clamped.

A further object of the invention is to provide a clamping tool ofimproved and simplified construction with which a leakproof connectionbetween two sections of pipe may be effected with a minimum of time andeffort.

With the above and other objects in view which will appear as thedescription proceeds, the invention consists in the novel featuresherein set forth, illustrated in the accompanying drawings, and moreparticularly pointed out in the appended claims.

THE DRAWINGS Referring to the drawings in which numerals of likecharacter designate similar parts throughout the several views:

FIG. 1 is a perspective view of the tool comprising the invention;

FIG. 2 is a view of the tool in side elevation;

FIG. 3 is a plan view of the tool;

FIG. 4 is a transverse sectional view taken on line 4-4 of FIG. 3;

FIG. 5 is a perspective view of a typical wire clamp and coupling withwhich the tool of the invention is employed;

FIG. 6 is a view of the tool in the initial loop-tightening position onthe wire clamp; and

FIG. 7 is an enlarged view of the tool in its final clamping positionwith respect to the wire clamp.

As will be seen from FIG. 5, the numerals l0 and 11 represent twosections of pipe to be coupled in longitudinal alignment with a couplingsleeve or bushing 12 of compressible, leakproof material, such asrubber, bridging the adjacent ends of the two pipe sections. In the formof coupling for which the present tool was primarily designed, aflexible, corrugated band 13 of stainless steel or similar material,such as disclosed in the US. Pat. No. 3,233,922, to Evans, issued Feb.8, 1966, overlies the sleeve 12 with its ends overlapping.

A wire clamp generally represented by the numeral 14 comprises a singlestrand of wire of suitable dimensions bent in the form of a U" toprovide a bight 15 with leg portions 16 and 17 coiled around thecoupling one or more times with the shanks 16a and 17a of the coiled legportions passing through and under the bight 15. The coils are thentightened and clamped by the use of the tool of the present invention.When the coils are sufficiently tight to clamp the coupling in leakproofengagement with the pipe sections, the shanks of the coiled leg portionsare bent back over the bight portion to lock the coils in theirtightened positions.

Referring now to FIGS. 1-4 which represent the tool per se, the frame ofthe tool, generally represented by the numeral 18, comprises twolongitudinally extending, laterally spaced rails 19 secured at one endby a crosshead 20 and at their opposite ends by a base member 21. Athreaded shaft 22, lying between the'spaced rails 19, is supported atone end for free rotation by the crosshead 20, its opposite end, in theform of the invention shown, terminating short of the base member 21. Anunthreaded portion of the shaft 22 extends through the crosshead 20 andcarries a torque-limiting device 23 of any suitable type and isrotatable by a handle 24 through the torque-limiting device 23.

A pulling block 25 threadedly engages the shaft 22 and is longitudinallymovable on the shaft by rotation of the latter, said block beingarcuately recessed on both sides as at 26 for slidable support by therails 19. A pair of shank-gripping blocks 27 and 28, to be described,are independently slidable on the rails 19 between the pulling block andthe base member 21, arcuately recessed portions 29 being provided in thesides of these blocks for guiding engagement with the rails 19. Theadjacent faces of these blocks are provided with complementary grooves30 to accommodate their free-sliding movement with respect to thethreaded shaft 22. A flexible, load-equalizing cable 31 is suitablyfixed at its opposite ends, as at 32, for example, by threaded terminalson the cable, to the independently slidable gripping blocks 27 and 28(FIG. 3), and its intermediate portion passes slidably through anarcuate groove 33 in the pulling block 25. A top plate 34 is fastened tothe block 25 by suitable screws 35 for retaining the cable 31 in placein the groove 33.

Extending longitudinally from the base member 21 is a fulcrum foot 36which protrudes beyond the frame and is provided at its extremity with atransverse pivot groove 37 which, as will later appear, pivotallyengages the bight between the loops of the wire clamp. On either side ofthe fulcrum foot, a grooved guide track 38 is provided for receiving anddirecting the protruding free shanks 16a and through passageways 39extending through the base member 21. These passageways 39 are alignedwith passageways 40 in the respective gripping blocks 27 and 28 whichultimately receive and grip the shanks 16a and 17a of the wire clamp.

Reference to FIG. 3 will show the shank-gripping mechanism of thegripping blocks 27 and 28, the top cover plate 41 of block 28 havingbeen removed. In each block, an internal pocket 42 is cut out toaccommodate a pivotally mounted cam element 43 having a serrated camsurface 44 which, when in normal position, intersects the shankpassageways 40. The cam element 43 is normally urged into grippingposition within the passageways 40 by a coil spring 45 projecting from awell 46 in the interior of the block. An upstanding lug 47 on the cam isengaged by the base 48 of a release lever 49, which extends through asuitable opening in the cover plate 41 for the block, the release lever49 being located outside of the gripping block adjacent the upper faceof the cover plate 41. The cover plates are retained in place on theblocks by suitable screws 50. Thus, when the shanks 16a, 170 areintroduced by guide tracks 38 through passageways 39 and intopassageways 40 of the gripping blocks, the cam elements 43 are rotatedagainst their springs by the shanks in directions to respectively clearthe passageways 40, and when a pulling force is exerted on the shanks,the cams 43 are automatically urged into engagement with the shanks tolock them within the respective passageways 40. After the tool hascompleted its tightening and clamping function, the shanks are releasedfrom the passageways 40 by simply rotating the release levers 49 to urgethe cam elements 43 in directions against their respective springs 45 toclear the passageways 40. As will be seen from FIG. 1, the releaselevers 49 are so arranged that they can be activated simultaneously bytwo fingers of one hand of the operator and squeezed together.Preferably, the entrance openings of the passageways 40 are inwardlybeveled as at 40a to facilitate the insertion of the free ends ofrespective shanks in the gripping blocks.

After the loops 16, 17 are finally tightened and clamped, it isdesirable to dispose of the excess lengths of the shanks 16a, 17a, andfor this purpose, the base member 21 is provided with a shank cutoffdevice which, in the form of the invention illustrated, comprises a bore51 which extends through a portion of the base member in a directiontransverse to the passageways 39 and intersecting the same so that theshanks 16a, 17a pass through the bore, as seen in FIGS. 6 and 7. A boss52 (FIGS. 1 and 3), formed integrally with the base member 21, projectslaterally from one side of the frame and rotatably supports a cuttingbar 53 which extends longitudinally through the bore 51. That portion ofthe cutting bar which intersects the passageways 39 is particircular incross section to form a knife portion 54. An arcuate slot 55 is providedin the periphery of the boss 52 to receive a cutter lever 56 forconnection at one end of the rotary cutter bar 53. Thus, upon rotationof the cutter bar 53 in clockwise direction, as viewed in FlG. 7, thecutting edge of its knife 54 severs the shank 17a extending throughpassageway 39 and bore 51. Normally, the lever 56 is in its lowermostposition at the bottom of the arcuate slot 55, which places the cuttingknife 54 in the upper area of the bore 51 as shown in FIGS. 1 and 2, sothat the shanks can pass freely through the bore 51. However, in thecutting operation, the lever 56 is raised to its uppermost position inthe slot 55 to actuate the cutting knife 54 across the passageways 39 asshown in FIG. 7.

In operation, the two sections of pipe 10 and 11 are placed inend-to-end position with the compressible sleeve 12 bridging thejunction, and the corrugated band 13 is wrapped around the sleeve 12.The clamping wire is then looped as at 16 and 17, FIG. 5, around thebank 13 with one loop adjacent each edge of the band and the shanks 16a,17a inserted under the bight 15 connecting the loops. The shanks 16a,17a are then inserted by way of the guideways 38 through the passageways39 in the base member 21 and then through the passageways 40 ofrespective gripping blocks 27, 28, where they are gripped by the camlocks 43 under the normal tension of the springs 45. By turning thehandle 24 on the threaded shaft 22, the latter is rotated in clockwisedirection to draw the pulling block 25 to the right, as viewed in FIG.6, and the pulling block, which is connected to the gripping blocks 27,28 by the freely slidable, load-equalizing cable 31, applies pullingforce to the independent gripping blocks which are now firmly engagedwith the respective shanks 16a, 17a. As before pointed out, due to thearcuate slot 33 in the pulling block through which the cable 31 slidesfreely, an equalized pulling force is applied to the independentgripping blocks. Thus, in the event of any nonuniformity in the diameterof one of the pipe sections l0, 11, for example, a sufficientindependent tightening force is applied to either loop 16 or 17 despitesuch irregularity or nonuniformity. This equalization of the pullingforce is, of course, effected simultaneously in one operation of thehandle 24 and threaded shaft 22.

After the loops have been sufficiently tightened about the corrugatedband 13, the tool 18 is bodily tilted or rotated in counterclockwisedirection, as seen in FIG. 7, approximately 145 about the bight 15 heldin the fulcrum groove 37 to firmly clamp the shanks 16a, 17a over thebight of the loops 16, 17.

The lever 56 of the cutting device is then elevated to rotate thecutting knife 54 clockwise (FIG. 7) and sever the excess lengths of theshanks 16a, 17a. Thereafter, by means of the levers 49 on the grippingblocks, the shanks are released from the passageways 40 after the toolis removed from the coupling. In order to firmly secure the clamped endsof the loops over the bight, the ends of the cutoff shanks may be bentdown onto the wrapped band 13.

It will be apparent that the present invention provides an improved andhighly effective wire loop clamping tool which automatically tightenstwo spaced loops of a single strand of wire with an equalized pullingforce, firmly secures the loops in their finally tightened positions,and then severs the excess lengths of loop shanks from the coupling.

A bottom cover 57 may be employed to protect the assembly from foreignmatter. Also, release levers 49 may be used to allow removal of the tooland coupling before the clamps are tightened for use of the couplingelsewhere.

From the foregoing, it is believed that the invention may be readilyunderstood by those skilled in the art without further description, itbeing borne in mind that numerous changes may be made in the detailsdisclosed without departing from the spirit of the invention.

We claim:

1. A tool for tightening and clamping around a pipe coupling a singlestrand of wire formed in two laterally spaced loops connected by anintegral bight with the free shanks of respective loops underlying saidbight, said tool comprising a frame, a threaded shaft rotatably mountedtherein, a fulcrum foot projecting longitudinally from one end of saidframe for pivotally engaging said bight, a pair of gripping blocksslidably mounted on said frame, one on either side of said threadedshaft for independent longitudinal movement free of the threads of saidshaft, for anchoring the free shanks extending fromrespective wireloops, a pulling block threadedly engaging said shaft, means forrotating said shaft, and load-equalizing means connecting said pullingblock to said gripping blocks, whereby, upon rotation of said shaft,said pulling block simultaneously and individually imparts to respectivegripping blocks and the wire shanks anchored therein an equalizedpulling force to independently tighten respective wire loops, the bodilyshifting of said tool in an arcuate path about said bight after saidloops are tightened serving to bend said shanks back over said bight tolock said loops in their tightened position.

2. A tool as claimed in claim 1, wherein said load-equalizing meanscomprises a flexible cable connected at opposite ends to respectivegripping blocks, the intermediate portion of said cable being slidablysupported by said pulling block.

3. A tool as claimed in claim 2, wherein said pulling block is providedwith an arcuate groove for slidably receiving the intermediate portionof said cable.

4. A tool as claimed in claim 1, wherein said frame includes a pair oflaterally spaced, longitudinally extending guide rails arranged toslidably support said gripping blocks and pulling block.

5. A tool as claimed in claim 1, wherein torque-limiting means areprovided between said threaded shaft and its rotating means.

6. A tool as claimed in claim 1, wherein said gripping blocks areprovided with passageways for slidably receiving said free shanks, andspring-urged cam means intersecting said passageways for gripping saidshanks.

7. A tool as claimed in claim 6, including manually operated means forreleasing said cam means.

8. A tool as claimed in claim 1, including cutting means on said framebetween said fulcrum foot and gripping blocks for severing the excesslengths of the shanks of said wire loops remaining after tightening andclamping.

9. A tool for and clamping around a pipe coupling a single strand ofwire formed in two laterally spaced loops connected by an integral bightwith the free shanks of respective loops underlying said bight, saidtool comprising a frame consisting of a pair of laterally spaced,longitudinally extending guide rails connected at opposite ends by acrosshead and a base member, a threaded shaft supported by and freelyrotatable in said crosshead, extending between and parallel with saidguide rails, a fulcrum foot projecting longitudinally from one end ofsaid frame adjacent said base member, said fulcrum foot presenting atransverse slot on its projecting end for pivotally engaging said bight,a pair of gripping blocks slidably supported by and between said guiderails, one on either side of said threaded shafi, said gripping blocksbeing free of the threads on said shaft, means on said gripping blocksfor receiving and anchoring the free shanks of respective wire loops, apulling block threadedly engaging said shaft, means for rotating saidshaft, load-equalizing means connecting said pulling block to saidgripping blocks, whereby, upon rotation of said shaft, said pullingblock simultaneously and individually imparts to respective grippingblocks and the wire shanks anchored therein an equalized pulling forceto independently tighten respective wire loops, the bodily shifting ofsaid tool in an arcuate path about said bight, after said loops aretightened, serving to bend said shanks back over said bight to lock saidloops in their tightened positions, and cutting means on said framebetween said fulcrum foot and gripping blocks for severing the excesslengths of the shanks of said wire loops remaining after tightening andclamping.

10. A tool as claimed in claim 9, wherein said base member includes aknife housing, shank-receiving passageways extending through saidhousing, a cutting knife in said housing having a cutting edge whichintersects said passageways, and means for actuating said cutting knife.

11. A tool as claimed in claim 9, wherein said base member is providedwith a bore running transversely of said frame, shank-receivingpassageways in said base member intersecting said bore, aparti-cylindrical cutting knife rotatable in said bore having a cuttingedge which intersects said passageways, and means for rotating saidknife in said bore.

1. A tool for tightening and clamping around a pipe coupling a singlestrand of wire formed in two laterally spaced loops connected by anintegral bight with the free shanks of respective loops underlying saidbight, said tool comprising a frame, a threaded shaft rotatably mountedtherein, a fulcrum foot prOjecting longitudinally from one end of saidframe for pivotally engaging said bight, a pair of gripping blocksslidably mounted on said frame, one on either side of said threadedshaft for independent longitudinal movement free of the threads of saidshaft, for anchoring the free shanks extending from respective wireloops, a pulling block threadedly engaging said shaft, means forrotating said shaft, and load-equalizing means connecting said pullingblock to said gripping blocks, whereby, upon rotation of said shaft,said pulling block simultaneously and individually imparts to respectivegripping blocks and the wire shanks anchored therein an equalizedpulling force to independently tighten respective wire loops, the bodilyshifting of said tool in an arcuate path about said bight after saidloops are tightened serving to bend said shanks back over said bight tolock said loops in their tightened position.
 2. A tool as claimed inclaim 1, wherein said load-equalizing means comprises a flexible cableconnected at opposite ends to respective gripping blocks, theintermediate portion of said cable being slidably supported by saidpulling block.
 3. A tool as claimed in claim 2, wherein said pullingblock is provided with an arcuate groove for slidably receiving theintermediate portion of said cable.
 4. A tool as claimed in claim 1,wherein said frame includes a pair of laterally spaced, longitudinallyextending guide rails arranged to slidably support said gripping blocksand pulling block.
 5. A tool as claimed in claim 1, whereintorque-limiting means are provided between said threaded shaft and itsrotating means.
 6. A tool as claimed in claim 1, wherein said grippingblocks are provided with passageways for slidably receiving said freeshanks, and spring-urged cam means intersecting said passageways forgripping said shanks.
 7. A tool as claimed in claim 6, includingmanually operated means for releasing said cam means.
 8. A tool asclaimed in claim 1, including cutting means on said frame between saidfulcrum foot and gripping blocks for severing the excess lengths of theshanks of said wire loops remaining after tightening and clamping.
 9. Atool for and clamping around a pipe coupling a single strand of wireformed in two laterally spaced loops connected by an integral bight withthe free shanks of respective loops underlying said bight, said toolcomprising a frame consisting of a pair of laterally spaced,longitudinally extending guide rails connected at opposite ends by acrosshead and a base member, a threaded shaft supported by and freelyrotatable in said crosshead, extending between and parallel with saidguide rails, a fulcrum foot projecting longitudinally from one end ofsaid frame adjacent said base member, said fulcrum foot presenting atransverse slot on its projecting end for pivotally engaging said bight,a pair of gripping blocks slidably supported by and between said guiderails, one on either side of said threaded shaft, said gripping blocksbeing free of the threads on said shaft, means on said gripping blocksfor receiving and anchoring the free shanks of respective wire loops, apulling block threadedly engaging said shaft, means for rotating saidshaft, load-equalizing means connecting said pulling block to saidgripping blocks, whereby, upon rotation of said shaft, said pullingblock simultaneously and individually imparts to respective grippingblocks and the wire shanks anchored therein an equalized pulling forceto independently tighten respective wire loops, the bodily shifting ofsaid tool in an arcuate path about said bight, after said loops aretightened, serving to bend said shanks back over said bight to lock saidloops in their tightened positions, and cutting means on said framebetween said fulcrum foot and gripping blocks for severing the excesslengths of the shanks of said wire loops remaining after tightening andclamping.
 10. A tool as claimed in claim 9, wherein said base memberincludes a knife housing, shank-receiving passageways extending throughsaid housing, a cutting knife in said housing having a cutting edgewhich intersects said passageways, and means for actuating said cuttingknife.
 11. A tool as claimed in claim 9, wherein said base member isprovided with a bore running transversely of said frame, shank-receivingpassageways in said base member intersecting said bore, aparti-cylindrical cutting knife rotatable in said bore having a cuttingedge which intersects said passageways, and means for rotating saidknife in said bore.